Apple is offering a new tool that lets potential buyers of a used iPhone, iPad, and iPod know if the devices was previously stolen.

The new Activation Lock Status tool, available through the company's iCloud service, allows users to enter the device's serial number and see if used devices are currently locked down or have ever been locked down by a previous owner, which would indicate the device was stolen. The reason behind the feature? Few customers would buy stolen devices, especially ones they can't use, so thieves will be deterred from stealing them in the first place.

Apple introduced its "kill switch" feature with iOS 7 last September. Using the Find My iPhone app and iCloud.com, users can track their phone's location, in case it was accidentally left somewhere. Or, for those who believe their phone was stolen, they can enable the kill switch, which locks down the phone. The app can also delete all of its data in case the phone contains sensitive information. The only way to re-enable the device once it is locked down is to enter its associated Apple ID and password.

Hackers figured out a way to unlock mobile and tablet devices by tricking the device into using an alternative iCloud server, writes PC World. That's where the new Activation Lock Status tool comes in. Even if hackers are able to trick the device into unlocking, potential customers can check if the device was ever locked from the Find My iPhone feature.

Mobile devices have a high robbery rate. In California, 1 in every 3 robberies includes a mobile device, according to the Federal Communications Commission. For Oakland, Calif., it's 75 percent of robberies. But Apple's locking feature has been extremely effective. In the months after the kill switch feature was released, iPhone thefts dropped 38 percent in San Francisco, according to a June law enforcement report. The robbery rate of Samsung phones, which don't have a kill switch feature, increased 12 percent.

In an attempt to cut down on the number of phones stolen across the state, California passed a law that will require all smart phones to have a kill switch system.

“Our efforts will effectively wipe out the incentive to steal smart phones and curb this crime of convenience, which is fueling street crime and violence within our communities," Sen. Mark Leno, who introduced the bill, said in a statement.